Learn when and where to find the Woolly Bear Caterpillar and how to observe this insect's interesting life cycle as it transforms into the Isabella Tiger Moth.
If you hunt for a Woolly Bear, you don’t need a gun. The Woolly Bear is a caterpillar. How about a tiger hunt instead? The woolly bear is the caterpillar of the Isabella Tiger Moth. So if you hunt for this black and red "bear" are you a bear hunter or a tiger hunter?
Neither one, of course! You are an insect hunter. We know moths and butterflies are categorized as insects because they have three main body regions, (head, thorax, and abdomen), three pairs of jointed legs, and one pair of antennae. Most insects also have two pairs of wings, while a few are wingless.
Wouldn’t it be fun to catch a Woolly Bear caterpillar and keep it alive in a jar, feed it everyday as it fattens and watch it? The caterpillar will hibernate through the cold part of winter. In the spring you can feed it again, watch it spin a cocoon of silk and hair. One week later it will “hatch” and the moth will emerge. Then you can set your Tiger moth free outside.
What Does the Bear Look Like?
The Woolly Bear is black and red. The head end and the back end are black and the center section is like a red belt. Think of the red belt as some sort of karate costume! This caterpillar differs from the caterpillar of the Great Leopard Moth, in that, the Great Leopard caterpillar has many narrower red bands circling its black length.
The Woolly Bear is thirteen segments long. Usually, the stubby “fur” covered caterpillars are black for the first four or five segments, red for four to six of the middle segments and the last two or three are black. They vary. The bear may appear to have only twelve segments (besides the head), but if you look carefully, you’ll notice that the last two are so closely joined they might be counted as one.
Bristly Bear Tubercules
The Woolly Bear’s hair sticks out like hairbrush bristles. Each tubercule holds a tiny bouquet called a rosette of hairs. These appear to be even lengths, but often there are a few longer hairs on the rear segment. These bristles protect the caterpillar from becoming dinner for a hungry bird. Birds don’t like bristles and when the bear is frightened or asleep it curls up into a little ball and is hard to pick up. Those bristles are like elastic and no easy for a beak to grasp.
True Legs
Wooley Bears have true legs, prolegs and proplegs. What is that? True legs are in three pairs on the three front segments. They have little shiny claws that help it grip leaf surfaces. The prolegs are on four of the abdominal segments and help the caterpillar move along. The prop-leg is on the rear segment and helps the caterpillar hold unto the leaves. These prolegs and prop-legs are not really legs, but elongations of the body.
Antenna, Spiracles, and Eyes
Woolly Bear’s heads are shiny black. They look like they have been polished with shoe polish. They have yellow antennae and yellow spots on either side of the first segments and the sides of eight of the abdominal segments. These are called spiracles and they are openings to air tubes which run through the caterpillar. The eyes of this caterpillar are minute. They are so small that the caterpillar cannot see much. He feels his way around by lifting the front section and moving it out and back and forth searching for something to climb on.
Food for a Bear
The Woolly Bear likes many different plants most especially grass, dandelion, and clover. He eats his way toward winter and then rolls up in a ball on the ground—not eating any more until spring. He eats the fresh spring grass and then proceeds to make a cocoon in April or as late as May. He spins the coon around himself and becomes a smooth little pupa inside a small felt like cocoon.
If you find a caterpillar put it in a box or breeding jar with plants and keep it outside where it will stay cold. Heat will likely kill it. A garage, playhouse, or in an unheated shed will protect it from big storms, but keep it cold.
Hatching Isabella
In the spring, give it some fresh grass every day and a stick or two and watch it make a cocoon and then watch as the Isabella Tiger Moth hatches out at the end of May. The moth is a dull grayish tawny yellow color. Look for black dots on the wings, dull orange-red tint on the hind wings plus a row of six black dots down the center of the body and on each side of the body is another row. These moths are night fliers and they fly off to a suitable food plant and lay eggs.
Keeping a record of your bears, when and where you found them, what they ate, when they wove cocoons, and when the moths hatched and were released, helps you learn about this caterpillar and can be turned into a great school science project. Share your knowledge about Woolly Bears with others, so they can enjoy this super-cool insect too.
For more moth information read another article about hatching cocoons.
The copyright of the article Woolly Bear Hunting in Kids Educational Activities is owned by Elece Hollis. Permission to republish Woolly Bear Hunting in print or online must be granted by the author in writing.
I just found a wooly bear caterpillar about4-5 days ago. It is so cool to
watch. It seems to like being outside. This is a great website. I
learned so much about my new caterpillar.
Oct 4, 2008 11:46 AM
Guest :
I have just found a totally black wooly bear. what does that mean? hard
winter?
Oct 6, 2008 1:01 PM
Elece Hollis :
I can't tell you what it means to find an all black woolly bear. It may
just be a abnormality. If he had very thin red rings, almost unnoticable
unless the caterpillar is curled up, he was a larva of the Great Leopard
moth. Butterflies and Moths (a Golden Guide) by Robert Mitchell and
Herbert Zim is a great help for studying.
Oct 16, 2008 7:26 AM
Guest :
i caught a wooly bear and put it in a cage with grass and soild and leaves.
but when i came out this morning the wooly bear was gone! so i searched the
cage and i found a green caterpillar. do they shed thier fur?
Oct 16, 2008 8:50 AM
Elece Hollis :
The green caterpillar is not a woolly bear that has shed. It is another
caterpillar that was in the leaves or which hatched from an egg on one of
the leaves. You just overlooked it. The woolly bear is either escaped or he
has crawled up on the back side of a leaf. The bear's camouflage is so
good, it may be hiding on the soil or along a twig. If it was in a cage
rather than a jar, something may have eaten it. Oh, dear!
Someone asked about watering a cocoon. Don't put water into the jar for a
caterpillar or cocoon. He gets his water from leaves. If the leaves dry out
too soon add fresh leaves of the same type.
Oct 20, 2008 12:07 PM
Guest :
I just found an all red wooly bear. What does that mean?
Oct 20, 2008 2:12 PM
Elece Hollis :
There are no red woolly bear caterpillars. It might be an Acrea Moth larva
called the Salt Marsh Caterpillar. People used to think if they found a
wooly bear a different color (like all black), it meant the winter would be
longer. Usually, it is a case of mistaken identity.
Jan 5, 2009 9:40 AM
Guest :
I found one of these caterpillars about 1 1/2 wks ago. It was right after a
big snow storm here and it was on my front step when I opened the door. I
have it in the house, but in a very cool spot so it doesn't get too hot.
What would you recommend giving it since just about all the grass and
plants are dead this time of year? I put some hay in it that our bunny
eats and it seems to be munching on that, but I want to make sure it is
being fed enough. Thank you
Jan 16, 2009 1:53 PM
Guest :
We found 2 Woolly Bear caterpillars late last fall. We put them in a jar
with plant cuttings, and later transferred them to a shoebox size animal
habitat/cage. We put dirt, the plant cuttings, and sprout seeds which grew
quickly. After awhile one caterpillar made a cocoon, and a day or 2 later
the other caterpillar attached his cocoon to the first. A few days ago the
1st moth emerged and laid several bunches of eggs. The next day the 2nd
moth emerged (though no more eggs). A day later the first moth died, and I
am worried about the 2nd. What can we feed it? I cant release it - it is
snowing we are experiencing the most frigid weather of the year with the
wind chill in the negatives. Any help is appreciated. Thanks!
Jan 16, 2009 3:32 PM
Elece Hollis :
Dear Friend, When you keep caterpillars or cocoons to watch them hatch, you
should keep them out in a shed or garage where they will be cold. Inside
the house the larva think it is spring (since it is warm and so they hatch
too soon). The moths only live a short time anyway after laying eggs.
Sorry. It sounds like you made a cool habitat though. from Mrs. Hollis
Feb 28, 2009 7:41 AM
Guest :
my brother found a woolly caterpillar today. it was really warm yesterday,
above 50, so i guess he woke up thinking it was spring. i don't know what
to do with him. i'm not sure if i should keep him inside or outside. we
have grass, hay and other food to give him, but i'm not sure what to do!
Aug 16, 2009 4:07 AM
Guest :
Hi, I have recently caught a wooly bear caterpillar and, it has turned
entirely black. Is this bad? It's very small (length) and it seems to be a
baby. Also, 1 and a half weeks ago I found a rather large wooly bear
caterpillar, it was an adult, but the next day, it was in it's cocoon! I'm
starting to worry because it hasn't come out yet! How long will it take for
it to come out? Is there a chance that it may be dead? Any ideas?
Well, thanks for helping! Bye!
Aug 30, 2009 5:58 AM
Guest :
I am making a 'trap' for woolly bear caterpillars. It is an upside-down
flowerpot with clover, grass, and leaves on top. If I can attract them,
though, we have a problem with our yard, and I can't keep it outside. Could
I put the jar in front of an open window, or in front of my fan?
